There’s nothing at all magical about this number. Reaching it doesn’t mean that Obamacare “works.” Surpassing the goal might have some effect on the federal budget (more signups, for example, presumably mean higher subsidy costs), but there’s no obvious correlation between the signup total and anything else.

There is still way more that we don’t know about this new world and the details matter a lot for insurers setting next year’s premiums. We don’t know, for example, how many of those who signed up will wind up paying premiums. We don’t know the mix of young and old. And until people start making claims, we also won't know the mix of healthy and unhealthy.

Nor do we know how many people overall are newly insured; how many are replacing canceled plans they were perfectly happy with; and how many were insured, but are finding better deals through the exchanges.

One more thing: At best, a slew of healthy signups might show that the law can function as (more or less) expected. That can’t prove whether it’s good or desirable policy.

I agree with Paul Krugman: expect a good deal of “unskewing” from conservatives who've been absolutely convinced for months that Obamacare was already a failure. As I tweeted yesterday, the busiest people this week are Republican operatives rationalizing why higher than expected enrollment is proof of failure. At any rate, healthy enrollment numbers should kill the preposterous Republican notion that people just don’t want health insurance.

"Success” and “failure” remain the wrong ways to think about Obamacare. Complete failure was always unlikely, and not even the most optimistic supporters thought the law would fix everything wrong with health care in the U.S. In the real world, what counts is how well the law performs, what its strengths and weaknesses prove to be, and what fixes would actually improve things.

To contact the writer of this article: Jonathan Bernstein at Jbernstein62@bloomberg.net.

To contact the editor responsible for this article: Francis Wilkinson at fwilkinson1@bloomberg.net.

Jonathan Bernstein is a Bloomberg View columnist covering U.S. politics. A political scientist, he previously wrote "A Plain Blog About Politics." He is co-editor of "The Making of the Presidential Candidates 2012."
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